4i6 



THE BLOOD. 



[OH. xxvi. 



the deer tribe and largest in the elephant. In the camelidae 

 they are biconvex. In all mammals the corpuscles are non- 

 nucleated, and in all other vertebrates (birds, reptiles, amphibia, 

 and fishes) the corpuscles are oval, biconvex, and nucleated 



Fig. 344. The above illustration is somewhat altered from a drawing by Gulliver, in the 

 Proceed. Zool. Society, and exhibits the typical characters of the red blood-cells in the 

 main divisions of the Vertebrata. The fractions are those of an inch, and represent 

 the average diameter. In the case of the oval cells, only the long diameter is here 

 given. It is remarkable, that although the size of the red blood-cells varies so much 

 in the different classes of the vertebrate kingdom, that of the white corpuscles remains 

 comparatively uniform, and thus they are, in some animals, larger, in others smaller, 

 than the red corpuscles. 



(fig. 344) and larger than in mammals. They are largest of all 

 in certain amphibians (amphiuma, proteus). 



The red corpuscles are not all alike, for in almost every speci- 

 men of blood may be also observed a certain number of corpuscles 

 smaller than the rest. They are termed microcytes, or haemato- 

 blasts, and are probably immature corpuscles. 



